release/src/router/busybox/archival/libarchive/decompress_unxz.c

   1 /*
   2  * This file uses XZ Embedded library code which is written
   3  * by Lasse Collin <lasse.collin@tukaani.org>
   4  * and Igor Pavlov <http://7-zip.org/>
   5  *
   6  * See README file in unxz/ directory for more information.
   7  *
   8  * This file is:
   9  * Copyright (C) 2010 Denys Vlasenko <vda.linux@googlemail.com>
  10  * Licensed under GPLv2, see file LICENSE in this source tree.
  11  */
  12 #include "libbb.h"
  13 #include "bb_archive.h"
  14
  15 #define XZ_FUNC FAST_FUNC
  16 #define XZ_EXTERN static
  17
  18 #define XZ_DEC_DYNALLOC
  19
  20 /* Skip check (rather than fail) of unsupported hash functions */
  21 #define XZ_DEC_ANY_CHECK  1
  22
  23 /* We use our own crc32 function */
  24 #define XZ_INTERNAL_CRC32 0
  25 static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc)
  26 {
  27         return ~crc32_block_endian0(~crc, buf, size, global_crc32_table);
  28 }
  29
  30 /* We use arch-optimized unaligned accessors */
  31 #define get_unaligned_le32(buf) ({ uint32_t v; move_from_unaligned32(v, buf); SWAP_LE32(v); })
  32 #define get_unaligned_be32(buf) ({ uint32_t v; move_from_unaligned32(v, buf); SWAP_BE32(v); })
  33 #define put_unaligned_le32(val, buf) move_to_unaligned16(buf, SWAP_LE32(val))
  34 #define put_unaligned_be32(val, buf) move_to_unaligned16(buf, SWAP_BE32(val))
  35
  36 #include "unxz/xz_dec_bcj.c"
  37 #include "unxz/xz_dec_lzma2.c"
  38 #include "unxz/xz_dec_stream.c"
  39
  40 IF_DESKTOP(long long) int FAST_FUNC
  41 unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
  42 {
  43         struct xz_buf iobuf;
  44         struct xz_dec *state;
  45         unsigned char *membuf;
  46         IF_DESKTOP(long long) int total = 0;
  47
  48         if (!global_crc32_table)
  49                 global_crc32_table = crc32_filltable(NULL, /*endian:*/ 0);
  50
  51         memset(&iobuf, 0, sizeof(iobuf));
  52         membuf = xmalloc(2 * BUFSIZ);
  53         iobuf.in = membuf;
  54         iobuf.out = membuf + BUFSIZ;
  55         iobuf.out_size = BUFSIZ;
  56
  57         if (!aux || aux->check_signature == 0) {
  58                 /* Preload XZ file signature */
  59                 strcpy((char*)membuf, HEADER_MAGIC);
  60                 iobuf.in_size = HEADER_MAGIC_SIZE;
  61         } /* else: let xz code read & check it */
  62
  63         /* Limit memory usage to about 64 MiB. */
  64         state = xz_dec_init(XZ_DYNALLOC, 64*1024*1024);
  65
  66         while (1) {
  67                 enum xz_ret r;
  68
  69                 if (iobuf.in_pos == iobuf.in_size) {
  70                         int rd = safe_read(src_fd, membuf, BUFSIZ);
  71                         if (rd < 0) {
  72                                 bb_error_msg(bb_msg_read_error);
  73                                 total = -1;
  74                                 break;
  75                         }
  76                         iobuf.in_size = rd;
  77                         iobuf.in_pos = 0;
  78                 }
  79 //              bb_error_msg(">in pos:%d size:%d out pos:%d size:%d",
  80 //                              iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size);
  81                 r = xz_dec_run(state, &iobuf);
  82 //              bb_error_msg("<in pos:%d size:%d out pos:%d size:%d r:%d",
  83 //                              iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, r);
  84                 if (iobuf.out_pos) {
  85                         xwrite(dst_fd, iobuf.out, iobuf.out_pos);
  86                         IF_DESKTOP(total += iobuf.out_pos;)
  87                         iobuf.out_pos = 0;
  88                 }
  89                 if (r == XZ_STREAM_END) {
  90                         break;
  91                 }
  92                 if (r != XZ_OK && r != XZ_UNSUPPORTED_CHECK) {
  93                         bb_error_msg("corrupted data");
  94                         total = -1;
  95                         break;
  96                 }
  97         }
  98         xz_dec_end(state);
  99         free(membuf);
 100
 101         return total;
 102 }